1. Field of the Invention
The present invention relates to an electronic device provided with a power control function.
2. Description of the Related Art
Electronic devices such as portable game devices, Personal Data Assistants (PDAs), or the like have become popular. Recent years, a number of electronic devices are equipped with a communication function. Further, multifunctional electronic devices such as smart phones, which combine functions of mobile phones, PDAs, or the like in one device, have come on the market.
[PATENT DOCUMENT No. 1] U.S. Pat. No. 7,558,820
Since mobile electronic devices are driven by a battery, it is preferable that the devices be capable of reducing unnecessary power consumption as much as possible. For this purpose, such an electronic device is typically equipped with a power saving function, and is configured so as to switch to a power saving state autonomously if the electronic device is not manipulated by a user for a predetermined time period. Meanwhile, some applications require to execute a predetermined process at regular time intervals even during a system suspend state. A mail application represents such an application. For example, a mail application requires to receive newly arrived emails on a regular basis from a mail server even if the electronic device is in the suspend state. This allows a user to browse most recent incoming emails right after the user returns the electronic device to an awake state.
In case that a plurality of applications exist that require system resume on a regular basis, if system resume occurs at high frequency, the battery consumption will increase, which may be a problem. Therefore, the emergence of a technology is desired, which efficiently sets the time of timer when resuming the system by timer control.
If the remaining battery level decreases below a predetermined value, the power is automatically switched off. A user charges an electronic device when he/she does not use the electronic device if there is a battery charger. However, as a result of charging an electronic device that has been turned off due to an insufficient battery level, the user has to push a power button so as to cold boot the system when the user uses the electronic device next time. If the user does not know that the electronic device has been powered off, the user is not aware of the necessity to cold boot. Thus, the user may feel discomfort when using the device next time.